Automobile assembling lines, for example, include a working process for automatically mounting a tire, which is one type of heavy component, onto an automobile body using a robot.
A tire mounting apparatus, which is applied to a working process of the type described above, usually has a tire gripper for gripping the tire, and a plurality of nut runners for tightening hub nuts onto the hub bolts of an automobile body.
As disclosed in Japanese Laid-Open Patent Publication No, 2000-210825, a tire mounting apparatus of the type described above includes a plurality of nut runners capable of placing as many nuts as the number of hub bolts of the motor vehicle at given circumferential intervals, a tire mounting mechanism for automatically mounting a tire onto the motor vehicle, a nut supply mechanism for supplying nuts in a vertical attitude one by one, and a nut arraying mechanism for placing the nuts supplied from the nut supply mechanism in a circular pattern at intervals corresponding to the circumferential intervals at which the nut runners are disposed in a circular pattern, and transferring the nuts to the nut runners.